Color is discerned by the nerve cells in the eye. The retina of the eye has two main types of cell, rods, which detect light levels and and motion and cones which differentiate colors.

Dogs are known for not seeing the same colors as we do. They have only two cone receptors. One of them is blue, and the other is yellow, this limited color perception is called dichromatic vision.

Dogs’ retinas have fewer cones than human eyes. And as a result, they cannot see another color.

We possess the ability to see red, blue and green (all 3 main primary colors), but dogs can only see one main primary color (blue), so they don't have the ability to see red and green. This means they cannot see a mixture of more colors. Dogs can see colors, but not with the same spectrum as people. For example the color re. Dogs cannot see red, instead they see a dark brownish-grey or black.

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